Since electrical power consumption has been small since light sources such as a backlight are not provided, reflective liquid crystal display devices have been widely used for various portable electronic apparatuses. However, in reflective liquid crystal display devices, since display is performed using outside light such as natural light or illumination light, there has been a problem in that it has been difficult to view the display in a dark place. Accordingly, a liquid crystal display device has been proposed in which display can be viewed in a bright place by using outside light, as is a general reflective liquid crystal display device, and can also be viewed in a dark place by using a built-in light source such as a backlight. That is, in the liquid crystal display device described above, a reflective and a transmissive display mode are both provided, and in accordance with ambient brightness, the reflective or transmissive display mode can be selectively used. As a result, while decreasing electrical power consumption, clear display can be performed when it is dark. Hereinafter, in this specification, this type of liquid crystal display device is called “transflective liquid crystal display device”.
In recent years, concomitant with advancement of portable electronic apparatuses, OA apparatuses, and the like, apparatuses having color liquid crystal displays have been requested. In addition, in the field of the transflective liquid crystal display apparatuses described above, color displays have been increasingly desired. As a transflective liquid crystal display device that can respond to the request described above, the structure in which a color filter is provided on one of an upper substrate and a lower substrate has been proposed. In the case of the this type of transflective color liquid crystal display device, in a reflective display mode, after passing through the color filter, outside light incident from the upper substrata side is reflected from a reflective layer and then passes again through the color filter. On the other hand, in a transmissive display mode, illumination light incident from the lower substrate side by lighting means such as a backlight passes through the color filter. In the general structure, in both a reflective display mode and a transmissive display mode, display has been performed using the same color filter.
In this type of transflective liquid crystal display device, as described above, incident light passes through the color filer twice in a reflective display mode and once in a transmissive display mode, thereby performing color display. Accordingly, for example, in the case in which the color filter having pale tints is used so as to preferentially display colors in a reflective display mode in which light passes twice through the color filter, it is difficult to obtain fine color display in a transmissive display mode in which incident light passes through the color filter only once. However, in order to solve the problem described above, in the case in which a color filter having dark tints are used so as to preferentially display colors in a transmissive display mode in which light passes once through the color filter, display in a reflective display mode in which incident light passes twice through the color filter becomes dark, and as a result, sufficient visibility cannot be obtained. As described above, in conventional transflective liquid crystal display devices, it has been difficult to perform display exhibiting fine colors and having high visibility in both a reflective display mode and a transmissive display mode.
The present invention was made in order to solve the problems described above, and an object of the present invention is to provide a transflective liquid crystal display device in which display exhibiting fine colors and having superior visibility can be performed in both a reflective and a transmissive display mode. In addition, the present invention has an object to provide a substrate assembly for forming the liquid crystal display device described above and to provide an electronic apparatus comprising the liquid crystal display device that has superior visibility.